1. Field of the Invention
The present invention relates generally to a method of optical proximity correction (OPC), and more particularly, to a method of optical proximity correction capable of improving the coverage of inter-connect patterns stacked on line patterns.
2. Description of the Prior Art
In the fabrication of semiconductors, semiconductor devices are connected by multiple interconnect layers at different levels. Interlayer connections of various conductive layers are achieved by interconnection means such as vias or contacts. Accordingly, in the design of integrated circuit (IC) layout for each level, it is essential to consider the interconnect relation and the layout alignment of upper and lower levels as well as the limitations induced by process capability. However, as the scale of integration for nowadays electronic devices continues to shrink, the critical dimension (CD) required for semiconductor devices becomes smaller. In this condition, it is quite difficult to design layouts having necessary critical dimensions for every component while still maintaining a precise alignment of the layouts and reliable interconnections between the conductive layers.